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Age calculator

Get exact age in completed years, months, and days for any date, plus the total elapsed days, which is a different answer entirely.

EV-T09

Calculate age exactly.

See completed years, months, days, and total elapsed days for any as-of date.

Formula and assumptions: Calendar age borrows the actual length of the preceding month. Total days are elapsed UTC calendar days, avoiding daylight-saving-time drift.

READYEnter a scenario, then calculate.
Method reference: NIST time and frequency ↗

COMMON WAYS TO ASK

QUICK ANSWER

What this calculator tells you.

Get completed years, the months and days remaining, and the total elapsed days for any as-of date. Those answer different questions and rarely agree.

WORKED EXAMPLE

Born 10 September 2000

INPUTAs of 1 September 2026
RESULT25 years, 11 months, 22 days — and 9,487 days in total
CHECK THE EDGE CASES

Questions people ask next.

Why is age in days not just years times 365?

Leap days add to the elapsed total without moving a birthday, so the two figures diverge steadily. Calendar age counts anniversaries; elapsed days count days.

How is a 29 February birthday handled?

The calculator reports neutral calendar arithmetic. Which date counts as the anniversary in a common year is a matter of local rule rather than mathematics.

CONTINUE CALCULATING

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